Documentation / git.txton commit Merge branch 'nd/attr-debug-fix' into maint (6d7c1c8)
   1git(1)
   2======
   3
   4NAME
   5----
   6git - the stupid content tracker
   7
   8
   9SYNOPSIS
  10--------
  11[verse]
  12'git' [--version] [--help] [-c <name>=<value>]
  13    [--exec-path[=<path>]] [--html-path] [--man-path] [--info-path]
  14    [-p|--paginate|--no-pager] [--no-replace-objects] [--bare]
  15    [--git-dir=<path>] [--work-tree=<path>] [--namespace=<name>]
  16    <command> [<args>]
  17
  18DESCRIPTION
  19-----------
  20Git is a fast, scalable, distributed revision control system with an
  21unusually rich command set that provides both high-level operations
  22and full access to internals.
  23
  24See linkgit:gittutorial[7] to get started, then see
  25link:everyday.html[Everyday Git] for a useful minimum set of
  26commands.  The link:user-manual.html[Git User's Manual] has a more
  27in-depth introduction.
  28
  29After you mastered the basic concepts, you can come back to this
  30page to learn what commands git offers.  You can learn more about
  31individual git commands with "git help command".  linkgit:gitcli[7]
  32manual page gives you an overview of the command line command syntax.
  33
  34Formatted and hyperlinked version of the latest git documentation
  35can be viewed at `http://git-htmldocs.googlecode.com/git/git.html`.
  36
  37ifdef::stalenotes[]
  38[NOTE]
  39============
  40
  41You are reading the documentation for the latest (possibly
  42unreleased) version of git, that is available from 'master'
  43branch of the `git.git` repository.
  44Documentation for older releases are available here:
  45
  46* link:v1.8.1.1/git.html[documentation for release 1.8.1.1]
  47
  48* release notes for
  49  link:RelNotes/1.8.1.1.txt[1.8.1.1],
  50  link:RelNotes/1.8.1.txt[1.8.1].
  51
  52* link:v1.8.0.3/git.html[documentation for release 1.8.0.3]
  53
  54* release notes for
  55  link:RelNotes/1.8.0.3.txt[1.8.0.3],
  56  link:RelNotes/1.8.0.2.txt[1.8.0.2],
  57  link:RelNotes/1.8.0.1.txt[1.8.0.1],
  58  link:RelNotes/1.8.0.txt[1.8.0].
  59
  60* link:v1.7.12.4/git.html[documentation for release 1.7.12.4]
  61
  62* release notes for
  63  link:RelNotes/1.7.12.4.txt[1.7.12.4],
  64  link:RelNotes/1.7.12.3.txt[1.7.12.3],
  65  link:RelNotes/1.7.12.2.txt[1.7.12.2],
  66  link:RelNotes/1.7.12.1.txt[1.7.12.1],
  67  link:RelNotes/1.7.12.txt[1.7.12].
  68
  69* link:v1.7.11.7/git.html[documentation for release 1.7.11.7]
  70
  71* release notes for
  72  link:RelNotes/1.7.11.7.txt[1.7.11.7],
  73  link:RelNotes/1.7.11.6.txt[1.7.11.6],
  74  link:RelNotes/1.7.11.5.txt[1.7.11.5],
  75  link:RelNotes/1.7.11.4.txt[1.7.11.4],
  76  link:RelNotes/1.7.11.3.txt[1.7.11.3],
  77  link:RelNotes/1.7.11.2.txt[1.7.11.2],
  78  link:RelNotes/1.7.11.1.txt[1.7.11.1],
  79  link:RelNotes/1.7.11.txt[1.7.11].
  80
  81* link:v1.7.10.5/git.html[documentation for release 1.7.10.5]
  82
  83* release notes for
  84  link:RelNotes/1.7.10.5.txt[1.7.10.5],
  85  link:RelNotes/1.7.10.4.txt[1.7.10.4],
  86  link:RelNotes/1.7.10.3.txt[1.7.10.3],
  87  link:RelNotes/1.7.10.2.txt[1.7.10.2],
  88  link:RelNotes/1.7.10.1.txt[1.7.10.1],
  89  link:RelNotes/1.7.10.txt[1.7.10].
  90
  91* link:v1.7.9.7/git.html[documentation for release 1.7.9.7]
  92
  93* release notes for
  94  link:RelNotes/1.7.9.7.txt[1.7.9.7],
  95  link:RelNotes/1.7.9.6.txt[1.7.9.6],
  96  link:RelNotes/1.7.9.5.txt[1.7.9.5],
  97  link:RelNotes/1.7.9.4.txt[1.7.9.4],
  98  link:RelNotes/1.7.9.3.txt[1.7.9.3],
  99  link:RelNotes/1.7.9.2.txt[1.7.9.2],
 100  link:RelNotes/1.7.9.1.txt[1.7.9.1],
 101  link:RelNotes/1.7.9.txt[1.7.9].
 102
 103* link:v1.7.8.6/git.html[documentation for release 1.7.8.6]
 104
 105* release notes for
 106  link:RelNotes/1.7.8.6.txt[1.7.8.6],
 107  link:RelNotes/1.7.8.5.txt[1.7.8.5],
 108  link:RelNotes/1.7.8.4.txt[1.7.8.4],
 109  link:RelNotes/1.7.8.3.txt[1.7.8.3],
 110  link:RelNotes/1.7.8.2.txt[1.7.8.2],
 111  link:RelNotes/1.7.8.1.txt[1.7.8.1],
 112  link:RelNotes/1.7.8.txt[1.7.8].
 113
 114* link:v1.7.7.7/git.html[documentation for release 1.7.7.7]
 115
 116* release notes for
 117  link:RelNotes/1.7.7.7.txt[1.7.7.7],
 118  link:RelNotes/1.7.7.6.txt[1.7.7.6],
 119  link:RelNotes/1.7.7.5.txt[1.7.7.5],
 120  link:RelNotes/1.7.7.4.txt[1.7.7.4],
 121  link:RelNotes/1.7.7.3.txt[1.7.7.3],
 122  link:RelNotes/1.7.7.2.txt[1.7.7.2],
 123  link:RelNotes/1.7.7.1.txt[1.7.7.1],
 124  link:RelNotes/1.7.7.txt[1.7.7].
 125
 126* link:v1.7.6.6/git.html[documentation for release 1.7.6.6]
 127
 128* release notes for
 129  link:RelNotes/1.7.6.6.txt[1.7.6.6],
 130  link:RelNotes/1.7.6.5.txt[1.7.6.5],
 131  link:RelNotes/1.7.6.4.txt[1.7.6.4],
 132  link:RelNotes/1.7.6.3.txt[1.7.6.3],
 133  link:RelNotes/1.7.6.2.txt[1.7.6.2],
 134  link:RelNotes/1.7.6.1.txt[1.7.6.1],
 135  link:RelNotes/1.7.6.txt[1.7.6].
 136
 137* link:v1.7.5.4/git.html[documentation for release 1.7.5.4]
 138
 139* release notes for
 140  link:RelNotes/1.7.5.4.txt[1.7.5.4],
 141  link:RelNotes/1.7.5.3.txt[1.7.5.3],
 142  link:RelNotes/1.7.5.2.txt[1.7.5.2],
 143  link:RelNotes/1.7.5.1.txt[1.7.5.1],
 144  link:RelNotes/1.7.5.txt[1.7.5].
 145
 146* link:v1.7.4.5/git.html[documentation for release 1.7.4.5]
 147
 148* release notes for
 149  link:RelNotes/1.7.4.5.txt[1.7.4.5],
 150  link:RelNotes/1.7.4.4.txt[1.7.4.4],
 151  link:RelNotes/1.7.4.3.txt[1.7.4.3],
 152  link:RelNotes/1.7.4.2.txt[1.7.4.2],
 153  link:RelNotes/1.7.4.1.txt[1.7.4.1],
 154  link:RelNotes/1.7.4.txt[1.7.4].
 155
 156* link:v1.7.3.5/git.html[documentation for release 1.7.3.5]
 157
 158* release notes for
 159  link:RelNotes/1.7.3.5.txt[1.7.3.5],
 160  link:RelNotes/1.7.3.4.txt[1.7.3.4],
 161  link:RelNotes/1.7.3.3.txt[1.7.3.3],
 162  link:RelNotes/1.7.3.2.txt[1.7.3.2],
 163  link:RelNotes/1.7.3.1.txt[1.7.3.1],
 164  link:RelNotes/1.7.3.txt[1.7.3].
 165
 166* link:v1.7.2.5/git.html[documentation for release 1.7.2.5]
 167
 168* release notes for
 169  link:RelNotes/1.7.2.5.txt[1.7.2.5],
 170  link:RelNotes/1.7.2.4.txt[1.7.2.4],
 171  link:RelNotes/1.7.2.3.txt[1.7.2.3],
 172  link:RelNotes/1.7.2.2.txt[1.7.2.2],
 173  link:RelNotes/1.7.2.1.txt[1.7.2.1],
 174  link:RelNotes/1.7.2.txt[1.7.2].
 175
 176* link:v1.7.1.4/git.html[documentation for release 1.7.1.4]
 177
 178* release notes for
 179  link:RelNotes/1.7.1.4.txt[1.7.1.4],
 180  link:RelNotes/1.7.1.3.txt[1.7.1.3],
 181  link:RelNotes/1.7.1.2.txt[1.7.1.2],
 182  link:RelNotes/1.7.1.1.txt[1.7.1.1],
 183  link:RelNotes/1.7.1.txt[1.7.1].
 184
 185* link:v1.7.0.9/git.html[documentation for release 1.7.0.9]
 186
 187* release notes for
 188  link:RelNotes/1.7.0.9.txt[1.7.0.9],
 189  link:RelNotes/1.7.0.8.txt[1.7.0.8],
 190  link:RelNotes/1.7.0.7.txt[1.7.0.7],
 191  link:RelNotes/1.7.0.6.txt[1.7.0.6],
 192  link:RelNotes/1.7.0.5.txt[1.7.0.5],
 193  link:RelNotes/1.7.0.4.txt[1.7.0.4],
 194  link:RelNotes/1.7.0.3.txt[1.7.0.3],
 195  link:RelNotes/1.7.0.2.txt[1.7.0.2],
 196  link:RelNotes/1.7.0.1.txt[1.7.0.1],
 197  link:RelNotes/1.7.0.txt[1.7.0].
 198
 199* link:v1.6.6.3/git.html[documentation for release 1.6.6.3]
 200
 201* release notes for
 202  link:RelNotes/1.6.6.3.txt[1.6.6.3],
 203  link:RelNotes/1.6.6.2.txt[1.6.6.2],
 204  link:RelNotes/1.6.6.1.txt[1.6.6.1],
 205  link:RelNotes/1.6.6.txt[1.6.6].
 206
 207* link:v1.6.5.9/git.html[documentation for release 1.6.5.9]
 208
 209* release notes for
 210  link:RelNotes/1.6.5.9.txt[1.6.5.9],
 211  link:RelNotes/1.6.5.8.txt[1.6.5.8],
 212  link:RelNotes/1.6.5.7.txt[1.6.5.7],
 213  link:RelNotes/1.6.5.6.txt[1.6.5.6],
 214  link:RelNotes/1.6.5.5.txt[1.6.5.5],
 215  link:RelNotes/1.6.5.4.txt[1.6.5.4],
 216  link:RelNotes/1.6.5.3.txt[1.6.5.3],
 217  link:RelNotes/1.6.5.2.txt[1.6.5.2],
 218  link:RelNotes/1.6.5.1.txt[1.6.5.1],
 219  link:RelNotes/1.6.5.txt[1.6.5].
 220
 221* link:v1.6.4.5/git.html[documentation for release 1.6.4.5]
 222
 223* release notes for
 224  link:RelNotes/1.6.4.5.txt[1.6.4.5],
 225  link:RelNotes/1.6.4.4.txt[1.6.4.4],
 226  link:RelNotes/1.6.4.3.txt[1.6.4.3],
 227  link:RelNotes/1.6.4.2.txt[1.6.4.2],
 228  link:RelNotes/1.6.4.1.txt[1.6.4.1],
 229  link:RelNotes/1.6.4.txt[1.6.4].
 230
 231* link:v1.6.3.4/git.html[documentation for release 1.6.3.4]
 232
 233* release notes for
 234  link:RelNotes/1.6.3.4.txt[1.6.3.4],
 235  link:RelNotes/1.6.3.3.txt[1.6.3.3],
 236  link:RelNotes/1.6.3.2.txt[1.6.3.2],
 237  link:RelNotes/1.6.3.1.txt[1.6.3.1],
 238  link:RelNotes/1.6.3.txt[1.6.3].
 239
 240* release notes for
 241  link:RelNotes/1.6.2.5.txt[1.6.2.5],
 242  link:RelNotes/1.6.2.4.txt[1.6.2.4],
 243  link:RelNotes/1.6.2.3.txt[1.6.2.3],
 244  link:RelNotes/1.6.2.2.txt[1.6.2.2],
 245  link:RelNotes/1.6.2.1.txt[1.6.2.1],
 246  link:RelNotes/1.6.2.txt[1.6.2].
 247
 248* link:v1.6.1.3/git.html[documentation for release 1.6.1.3]
 249
 250* release notes for
 251  link:RelNotes/1.6.1.3.txt[1.6.1.3],
 252  link:RelNotes/1.6.1.2.txt[1.6.1.2],
 253  link:RelNotes/1.6.1.1.txt[1.6.1.1],
 254  link:RelNotes/1.6.1.txt[1.6.1].
 255
 256* link:v1.6.0.6/git.html[documentation for release 1.6.0.6]
 257
 258* release notes for
 259  link:RelNotes/1.6.0.6.txt[1.6.0.6],
 260  link:RelNotes/1.6.0.5.txt[1.6.0.5],
 261  link:RelNotes/1.6.0.4.txt[1.6.0.4],
 262  link:RelNotes/1.6.0.3.txt[1.6.0.3],
 263  link:RelNotes/1.6.0.2.txt[1.6.0.2],
 264  link:RelNotes/1.6.0.1.txt[1.6.0.1],
 265  link:RelNotes/1.6.0.txt[1.6.0].
 266
 267* link:v1.5.6.6/git.html[documentation for release 1.5.6.6]
 268
 269* release notes for
 270  link:RelNotes/1.5.6.6.txt[1.5.6.6],
 271  link:RelNotes/1.5.6.5.txt[1.5.6.5],
 272  link:RelNotes/1.5.6.4.txt[1.5.6.4],
 273  link:RelNotes/1.5.6.3.txt[1.5.6.3],
 274  link:RelNotes/1.5.6.2.txt[1.5.6.2],
 275  link:RelNotes/1.5.6.1.txt[1.5.6.1],
 276  link:RelNotes/1.5.6.txt[1.5.6].
 277
 278* link:v1.5.5.6/git.html[documentation for release 1.5.5.6]
 279
 280* release notes for
 281  link:RelNotes/1.5.5.6.txt[1.5.5.6],
 282  link:RelNotes/1.5.5.5.txt[1.5.5.5],
 283  link:RelNotes/1.5.5.4.txt[1.5.5.4],
 284  link:RelNotes/1.5.5.3.txt[1.5.5.3],
 285  link:RelNotes/1.5.5.2.txt[1.5.5.2],
 286  link:RelNotes/1.5.5.1.txt[1.5.5.1],
 287  link:RelNotes/1.5.5.txt[1.5.5].
 288
 289* link:v1.5.4.7/git.html[documentation for release 1.5.4.7]
 290
 291* release notes for
 292  link:RelNotes/1.5.4.7.txt[1.5.4.7],
 293  link:RelNotes/1.5.4.6.txt[1.5.4.6],
 294  link:RelNotes/1.5.4.5.txt[1.5.4.5],
 295  link:RelNotes/1.5.4.4.txt[1.5.4.4],
 296  link:RelNotes/1.5.4.3.txt[1.5.4.3],
 297  link:RelNotes/1.5.4.2.txt[1.5.4.2],
 298  link:RelNotes/1.5.4.1.txt[1.5.4.1],
 299  link:RelNotes/1.5.4.txt[1.5.4].
 300
 301* link:v1.5.3.8/git.html[documentation for release 1.5.3.8]
 302
 303* release notes for
 304  link:RelNotes/1.5.3.8.txt[1.5.3.8],
 305  link:RelNotes/1.5.3.7.txt[1.5.3.7],
 306  link:RelNotes/1.5.3.6.txt[1.5.3.6],
 307  link:RelNotes/1.5.3.5.txt[1.5.3.5],
 308  link:RelNotes/1.5.3.4.txt[1.5.3.4],
 309  link:RelNotes/1.5.3.3.txt[1.5.3.3],
 310  link:RelNotes/1.5.3.2.txt[1.5.3.2],
 311  link:RelNotes/1.5.3.1.txt[1.5.3.1],
 312  link:RelNotes/1.5.3.txt[1.5.3].
 313
 314* link:v1.5.2.5/git.html[documentation for release 1.5.2.5]
 315
 316* release notes for
 317  link:RelNotes/1.5.2.5.txt[1.5.2.5],
 318  link:RelNotes/1.5.2.4.txt[1.5.2.4],
 319  link:RelNotes/1.5.2.3.txt[1.5.2.3],
 320  link:RelNotes/1.5.2.2.txt[1.5.2.2],
 321  link:RelNotes/1.5.2.1.txt[1.5.2.1],
 322  link:RelNotes/1.5.2.txt[1.5.2].
 323
 324* link:v1.5.1.6/git.html[documentation for release 1.5.1.6]
 325
 326* release notes for
 327  link:RelNotes/1.5.1.6.txt[1.5.1.6],
 328  link:RelNotes/1.5.1.5.txt[1.5.1.5],
 329  link:RelNotes/1.5.1.4.txt[1.5.1.4],
 330  link:RelNotes/1.5.1.3.txt[1.5.1.3],
 331  link:RelNotes/1.5.1.2.txt[1.5.1.2],
 332  link:RelNotes/1.5.1.1.txt[1.5.1.1],
 333  link:RelNotes/1.5.1.txt[1.5.1].
 334
 335* link:v1.5.0.7/git.html[documentation for release 1.5.0.7]
 336
 337* release notes for
 338  link:RelNotes/1.5.0.7.txt[1.5.0.7],
 339  link:RelNotes/1.5.0.6.txt[1.5.0.6],
 340  link:RelNotes/1.5.0.5.txt[1.5.0.5],
 341  link:RelNotes/1.5.0.3.txt[1.5.0.3],
 342  link:RelNotes/1.5.0.2.txt[1.5.0.2],
 343  link:RelNotes/1.5.0.1.txt[1.5.0.1],
 344  link:RelNotes/1.5.0.txt[1.5.0].
 345
 346* documentation for release link:v1.4.4.4/git.html[1.4.4.4],
 347  link:v1.3.3/git.html[1.3.3],
 348  link:v1.2.6/git.html[1.2.6],
 349  link:v1.0.13/git.html[1.0.13].
 350
 351============
 352
 353endif::stalenotes[]
 354
 355OPTIONS
 356-------
 357--version::
 358        Prints the git suite version that the 'git' program came from.
 359
 360--help::
 361        Prints the synopsis and a list of the most commonly used
 362        commands. If the option '--all' or '-a' is given then all
 363        available commands are printed. If a git command is named this
 364        option will bring up the manual page for that command.
 365+
 366Other options are available to control how the manual page is
 367displayed. See linkgit:git-help[1] for more information,
 368because `git --help ...` is converted internally into `git
 369help ...`.
 370
 371-c <name>=<value>::
 372        Pass a configuration parameter to the command. The value
 373        given will override values from configuration files.
 374        The <name> is expected in the same format as listed by
 375        'git config' (subkeys separated by dots).
 376
 377--exec-path[=<path>]::
 378        Path to wherever your core git programs are installed.
 379        This can also be controlled by setting the GIT_EXEC_PATH
 380        environment variable. If no path is given, 'git' will print
 381        the current setting and then exit.
 382
 383--html-path::
 384        Print the path, without trailing slash, where git's HTML
 385        documentation is installed and exit.
 386
 387--man-path::
 388        Print the manpath (see `man(1)`) for the man pages for
 389        this version of git and exit.
 390
 391--info-path::
 392        Print the path where the Info files documenting this
 393        version of git are installed and exit.
 394
 395-p::
 396--paginate::
 397        Pipe all output into 'less' (or if set, $PAGER) if standard
 398        output is a terminal.  This overrides the `pager.<cmd>`
 399        configuration options (see the "Configuration Mechanism" section
 400        below).
 401
 402--no-pager::
 403        Do not pipe git output into a pager.
 404
 405--git-dir=<path>::
 406        Set the path to the repository. This can also be controlled by
 407        setting the GIT_DIR environment variable. It can be an absolute
 408        path or relative path to current working directory.
 409
 410--work-tree=<path>::
 411        Set the path to the working tree. It can be an absolute path
 412        or a path relative to the current working directory.
 413        This can also be controlled by setting the GIT_WORK_TREE
 414        environment variable and the core.worktree configuration
 415        variable (see core.worktree in linkgit:git-config[1] for a
 416        more detailed discussion).
 417
 418--namespace=<path>::
 419        Set the git namespace.  See linkgit:gitnamespaces[7] for more
 420        details.  Equivalent to setting the `GIT_NAMESPACE` environment
 421        variable.
 422
 423--bare::
 424        Treat the repository as a bare repository.  If GIT_DIR
 425        environment is not set, it is set to the current working
 426        directory.
 427
 428--no-replace-objects::
 429        Do not use replacement refs to replace git objects. See
 430        linkgit:git-replace[1] for more information.
 431
 432
 433GIT COMMANDS
 434------------
 435
 436We divide git into high level ("porcelain") commands and low level
 437("plumbing") commands.
 438
 439High-level commands (porcelain)
 440-------------------------------
 441
 442We separate the porcelain commands into the main commands and some
 443ancillary user utilities.
 444
 445Main porcelain commands
 446~~~~~~~~~~~~~~~~~~~~~~~
 447
 448include::cmds-mainporcelain.txt[]
 449
 450Ancillary Commands
 451~~~~~~~~~~~~~~~~~~
 452Manipulators:
 453
 454include::cmds-ancillarymanipulators.txt[]
 455
 456Interrogators:
 457
 458include::cmds-ancillaryinterrogators.txt[]
 459
 460
 461Interacting with Others
 462~~~~~~~~~~~~~~~~~~~~~~~
 463
 464These commands are to interact with foreign SCM and with other
 465people via patch over e-mail.
 466
 467include::cmds-foreignscminterface.txt[]
 468
 469
 470Low-level commands (plumbing)
 471-----------------------------
 472
 473Although git includes its
 474own porcelain layer, its low-level commands are sufficient to support
 475development of alternative porcelains.  Developers of such porcelains
 476might start by reading about linkgit:git-update-index[1] and
 477linkgit:git-read-tree[1].
 478
 479The interface (input, output, set of options and the semantics)
 480to these low-level commands are meant to be a lot more stable
 481than Porcelain level commands, because these commands are
 482primarily for scripted use.  The interface to Porcelain commands
 483on the other hand are subject to change in order to improve the
 484end user experience.
 485
 486The following description divides
 487the low-level commands into commands that manipulate objects (in
 488the repository, index, and working tree), commands that interrogate and
 489compare objects, and commands that move objects and references between
 490repositories.
 491
 492
 493Manipulation commands
 494~~~~~~~~~~~~~~~~~~~~~
 495
 496include::cmds-plumbingmanipulators.txt[]
 497
 498
 499Interrogation commands
 500~~~~~~~~~~~~~~~~~~~~~~
 501
 502include::cmds-plumbinginterrogators.txt[]
 503
 504In general, the interrogate commands do not touch the files in
 505the working tree.
 506
 507
 508Synching repositories
 509~~~~~~~~~~~~~~~~~~~~~
 510
 511include::cmds-synchingrepositories.txt[]
 512
 513The following are helper commands used by the above; end users
 514typically do not use them directly.
 515
 516include::cmds-synchelpers.txt[]
 517
 518
 519Internal helper commands
 520~~~~~~~~~~~~~~~~~~~~~~~~
 521
 522These are internal helper commands used by other commands; end
 523users typically do not use them directly.
 524
 525include::cmds-purehelpers.txt[]
 526
 527
 528Configuration Mechanism
 529-----------------------
 530
 531Starting from 0.99.9 (actually mid 0.99.8.GIT), `.git/config` file
 532is used to hold per-repository configuration options.  It is a
 533simple text file modeled after `.ini` format familiar to some
 534people.  Here is an example:
 535
 536------------
 537#
 538# A '#' or ';' character indicates a comment.
 539#
 540
 541; core variables
 542[core]
 543        ; Don't trust file modes
 544        filemode = false
 545
 546; user identity
 547[user]
 548        name = "Junio C Hamano"
 549        email = "junkio@twinsun.com"
 550
 551------------
 552
 553Various commands read from the configuration file and adjust
 554their operation accordingly.  See linkgit:git-config[1] for a
 555list.
 556
 557
 558Identifier Terminology
 559----------------------
 560<object>::
 561        Indicates the object name for any type of object.
 562
 563<blob>::
 564        Indicates a blob object name.
 565
 566<tree>::
 567        Indicates a tree object name.
 568
 569<commit>::
 570        Indicates a commit object name.
 571
 572<tree-ish>::
 573        Indicates a tree, commit or tag object name.  A
 574        command that takes a <tree-ish> argument ultimately wants to
 575        operate on a <tree> object but automatically dereferences
 576        <commit> and <tag> objects that point at a <tree>.
 577
 578<commit-ish>::
 579        Indicates a commit or tag object name.  A
 580        command that takes a <commit-ish> argument ultimately wants to
 581        operate on a <commit> object but automatically dereferences
 582        <tag> objects that point at a <commit>.
 583
 584<type>::
 585        Indicates that an object type is required.
 586        Currently one of: `blob`, `tree`, `commit`, or `tag`.
 587
 588<file>::
 589        Indicates a filename - almost always relative to the
 590        root of the tree structure `GIT_INDEX_FILE` describes.
 591
 592Symbolic Identifiers
 593--------------------
 594Any git command accepting any <object> can also use the following
 595symbolic notation:
 596
 597HEAD::
 598        indicates the head of the current branch.
 599
 600<tag>::
 601        a valid tag 'name'
 602        (i.e. a `refs/tags/<tag>` reference).
 603
 604<head>::
 605        a valid head 'name'
 606        (i.e. a `refs/heads/<head>` reference).
 607
 608For a more complete list of ways to spell object names, see
 609"SPECIFYING REVISIONS" section in linkgit:gitrevisions[7].
 610
 611
 612File/Directory Structure
 613------------------------
 614
 615Please see the linkgit:gitrepository-layout[5] document.
 616
 617Read linkgit:githooks[5] for more details about each hook.
 618
 619Higher level SCMs may provide and manage additional information in the
 620`$GIT_DIR`.
 621
 622
 623Terminology
 624-----------
 625Please see linkgit:gitglossary[7].
 626
 627
 628Environment Variables
 629---------------------
 630Various git commands use the following environment variables:
 631
 632The git Repository
 633~~~~~~~~~~~~~~~~~~
 634These environment variables apply to 'all' core git commands. Nb: it
 635is worth noting that they may be used/overridden by SCMS sitting above
 636git so take care if using Cogito etc.
 637
 638'GIT_INDEX_FILE'::
 639        This environment allows the specification of an alternate
 640        index file. If not specified, the default of `$GIT_DIR/index`
 641        is used.
 642
 643'GIT_OBJECT_DIRECTORY'::
 644        If the object storage directory is specified via this
 645        environment variable then the sha1 directories are created
 646        underneath - otherwise the default `$GIT_DIR/objects`
 647        directory is used.
 648
 649'GIT_ALTERNATE_OBJECT_DIRECTORIES'::
 650        Due to the immutable nature of git objects, old objects can be
 651        archived into shared, read-only directories. This variable
 652        specifies a ":" separated (on Windows ";" separated) list
 653        of git object directories which can be used to search for git
 654        objects. New objects will not be written to these directories.
 655
 656'GIT_DIR'::
 657        If the 'GIT_DIR' environment variable is set then it
 658        specifies a path to use instead of the default `.git`
 659        for the base of the repository.
 660        The '--git-dir' command-line option also sets this value.
 661
 662'GIT_WORK_TREE'::
 663        Set the path to the working tree.  The value will not be
 664        used in combination with repositories found automatically in
 665        a .git directory (i.e. $GIT_DIR is not set).
 666        This can also be controlled by the '--work-tree' command line
 667        option and the core.worktree configuration variable.
 668
 669'GIT_NAMESPACE'::
 670        Set the git namespace; see linkgit:gitnamespaces[7] for details.
 671        The '--namespace' command-line option also sets this value.
 672
 673'GIT_CEILING_DIRECTORIES'::
 674        This should be a colon-separated list of absolute paths.
 675        If set, it is a list of directories that git should not chdir
 676        up into while looking for a repository directory.
 677        It will not exclude the current working directory or
 678        a GIT_DIR set on the command line or in the environment.
 679        (Useful for excluding slow-loading network directories.)
 680
 681'GIT_DISCOVERY_ACROSS_FILESYSTEM'::
 682        When run in a directory that does not have ".git" repository
 683        directory, git tries to find such a directory in the parent
 684        directories to find the top of the working tree, but by default it
 685        does not cross filesystem boundaries.  This environment variable
 686        can be set to true to tell git not to stop at filesystem
 687        boundaries.  Like 'GIT_CEILING_DIRECTORIES', this will not affect
 688        an explicit repository directory set via 'GIT_DIR' or on the
 689        command line.
 690
 691git Commits
 692~~~~~~~~~~~
 693'GIT_AUTHOR_NAME'::
 694'GIT_AUTHOR_EMAIL'::
 695'GIT_AUTHOR_DATE'::
 696'GIT_COMMITTER_NAME'::
 697'GIT_COMMITTER_EMAIL'::
 698'GIT_COMMITTER_DATE'::
 699'EMAIL'::
 700        see linkgit:git-commit-tree[1]
 701
 702git Diffs
 703~~~~~~~~~
 704'GIT_DIFF_OPTS'::
 705        Only valid setting is "--unified=??" or "-u??" to set the
 706        number of context lines shown when a unified diff is created.
 707        This takes precedence over any "-U" or "--unified" option
 708        value passed on the git diff command line.
 709
 710'GIT_EXTERNAL_DIFF'::
 711        When the environment variable 'GIT_EXTERNAL_DIFF' is set, the
 712        program named by it is called, instead of the diff invocation
 713        described above.  For a path that is added, removed, or modified,
 714        'GIT_EXTERNAL_DIFF' is called with 7 parameters:
 715
 716        path old-file old-hex old-mode new-file new-hex new-mode
 717+
 718where:
 719
 720        <old|new>-file:: are files GIT_EXTERNAL_DIFF can use to read the
 721                         contents of <old|new>,
 722        <old|new>-hex:: are the 40-hexdigit SHA1 hashes,
 723        <old|new>-mode:: are the octal representation of the file modes.
 724+
 725The file parameters can point at the user's working file
 726(e.g. `new-file` in "git-diff-files"), `/dev/null` (e.g. `old-file`
 727when a new file is added), or a temporary file (e.g. `old-file` in the
 728index).  'GIT_EXTERNAL_DIFF' should not worry about unlinking the
 729temporary file --- it is removed when 'GIT_EXTERNAL_DIFF' exits.
 730+
 731For a path that is unmerged, 'GIT_EXTERNAL_DIFF' is called with 1
 732parameter, <path>.
 733
 734other
 735~~~~~
 736'GIT_MERGE_VERBOSITY'::
 737        A number controlling the amount of output shown by
 738        the recursive merge strategy.  Overrides merge.verbosity.
 739        See linkgit:git-merge[1]
 740
 741'GIT_PAGER'::
 742        This environment variable overrides `$PAGER`. If it is set
 743        to an empty string or to the value "cat", git will not launch
 744        a pager.  See also the `core.pager` option in
 745        linkgit:git-config[1].
 746
 747'GIT_EDITOR'::
 748        This environment variable overrides `$EDITOR` and `$VISUAL`.
 749        It is used by several git commands when, on interactive mode,
 750        an editor is to be launched. See also linkgit:git-var[1]
 751        and the `core.editor` option in linkgit:git-config[1].
 752
 753'GIT_SSH'::
 754        If this environment variable is set then 'git fetch'
 755        and 'git push' will use this command instead
 756        of 'ssh' when they need to connect to a remote system.
 757        The '$GIT_SSH' command will be given exactly two arguments:
 758        the 'username@host' (or just 'host') from the URL and the
 759        shell command to execute on that remote system.
 760+
 761To pass options to the program that you want to list in GIT_SSH
 762you will need to wrap the program and options into a shell script,
 763then set GIT_SSH to refer to the shell script.
 764+
 765Usually it is easier to configure any desired options through your
 766personal `.ssh/config` file.  Please consult your ssh documentation
 767for further details.
 768
 769'GIT_ASKPASS'::
 770        If this environment variable is set, then git commands which need to
 771        acquire passwords or passphrases (e.g. for HTTP or IMAP authentication)
 772        will call this program with a suitable prompt as command line argument
 773        and read the password from its STDOUT. See also the 'core.askpass'
 774        option in linkgit:git-config[1].
 775
 776'GIT_CONFIG_NOSYSTEM'::
 777        Whether to skip reading settings from the system-wide
 778        `$(prefix)/etc/gitconfig` file.  This environment variable can
 779        be used along with `$HOME` and `$XDG_CONFIG_HOME` to create a
 780        predictable environment for a picky script, or you can set it
 781        temporarily to avoid using a buggy `/etc/gitconfig` file while
 782        waiting for someone with sufficient permissions to fix it.
 783
 784'GIT_FLUSH'::
 785        If this environment variable is set to "1", then commands such
 786        as 'git blame' (in incremental mode), 'git rev-list', 'git log',
 787        and 'git whatchanged' will force a flush of the output stream
 788        after each commit-oriented record have been flushed.   If this
 789        variable is set to "0", the output of these commands will be done
 790        using completely buffered I/O.   If this environment variable is
 791        not set, git will choose buffered or record-oriented flushing
 792        based on whether stdout appears to be redirected to a file or not.
 793
 794'GIT_TRACE'::
 795        If this variable is set to "1", "2" or "true" (comparison
 796        is case insensitive), git will print `trace:` messages on
 797        stderr telling about alias expansion, built-in command
 798        execution and external command execution.
 799        If this variable is set to an integer value greater than 1
 800        and lower than 10 (strictly) then git will interpret this
 801        value as an open file descriptor and will try to write the
 802        trace messages into this file descriptor.
 803        Alternatively, if this variable is set to an absolute path
 804        (starting with a '/' character), git will interpret this
 805        as a file path and will try to write the trace messages
 806        into it.
 807
 808Discussion[[Discussion]]
 809------------------------
 810
 811More detail on the following is available from the
 812link:user-manual.html#git-concepts[git concepts chapter of the
 813user-manual] and linkgit:gitcore-tutorial[7].
 814
 815A git project normally consists of a working directory with a ".git"
 816subdirectory at the top level.  The .git directory contains, among other
 817things, a compressed object database representing the complete history
 818of the project, an "index" file which links that history to the current
 819contents of the working tree, and named pointers into that history such
 820as tags and branch heads.
 821
 822The object database contains objects of three main types: blobs, which
 823hold file data; trees, which point to blobs and other trees to build up
 824directory hierarchies; and commits, which each reference a single tree
 825and some number of parent commits.
 826
 827The commit, equivalent to what other systems call a "changeset" or
 828"version", represents a step in the project's history, and each parent
 829represents an immediately preceding step.  Commits with more than one
 830parent represent merges of independent lines of development.
 831
 832All objects are named by the SHA1 hash of their contents, normally
 833written as a string of 40 hex digits.  Such names are globally unique.
 834The entire history leading up to a commit can be vouched for by signing
 835just that commit.  A fourth object type, the tag, is provided for this
 836purpose.
 837
 838When first created, objects are stored in individual files, but for
 839efficiency may later be compressed together into "pack files".
 840
 841Named pointers called refs mark interesting points in history.  A ref
 842may contain the SHA1 name of an object or the name of another ref.  Refs
 843with names beginning `ref/head/` contain the SHA1 name of the most
 844recent commit (or "head") of a branch under development.  SHA1 names of
 845tags of interest are stored under `ref/tags/`.  A special ref named
 846`HEAD` contains the name of the currently checked-out branch.
 847
 848The index file is initialized with a list of all paths and, for each
 849path, a blob object and a set of attributes.  The blob object represents
 850the contents of the file as of the head of the current branch.  The
 851attributes (last modified time, size, etc.) are taken from the
 852corresponding file in the working tree.  Subsequent changes to the
 853working tree can be found by comparing these attributes.  The index may
 854be updated with new content, and new commits may be created from the
 855content stored in the index.
 856
 857The index is also capable of storing multiple entries (called "stages")
 858for a given pathname.  These stages are used to hold the various
 859unmerged version of a file when a merge is in progress.
 860
 861FURTHER DOCUMENTATION
 862---------------------
 863
 864See the references in the "description" section to get started
 865using git.  The following is probably more detail than necessary
 866for a first-time user.
 867
 868The link:user-manual.html#git-concepts[git concepts chapter of the
 869user-manual] and linkgit:gitcore-tutorial[7] both provide
 870introductions to the underlying git architecture.
 871
 872See linkgit:gitworkflows[7] for an overview of recommended workflows.
 873
 874See also the link:howto-index.html[howto] documents for some useful
 875examples.
 876
 877The internals are documented in the
 878link:technical/api-index.html[GIT API documentation].
 879
 880Users migrating from CVS may also want to
 881read linkgit:gitcvs-migration[7].
 882
 883
 884Authors
 885-------
 886Git was started by Linus Torvalds, and is currently maintained by Junio
 887C Hamano. Numerous contributions have come from the git mailing list
 888<git@vger.kernel.org>.  http://www.ohloh.net/p/git/contributors/summary
 889gives you a more complete list of contributors.
 890
 891If you have a clone of git.git itself, the
 892output of linkgit:git-shortlog[1] and linkgit:git-blame[1] can show you
 893the authors for specific parts of the project.
 894
 895Reporting Bugs
 896--------------
 897
 898Report bugs to the Git mailing list <git@vger.kernel.org> where the
 899development and maintenance is primarily done.  You do not have to be
 900subscribed to the list to send a message there.
 901
 902SEE ALSO
 903--------
 904linkgit:gittutorial[7], linkgit:gittutorial-2[7],
 905link:everyday.html[Everyday Git], linkgit:gitcvs-migration[7],
 906linkgit:gitglossary[7], linkgit:gitcore-tutorial[7],
 907linkgit:gitcli[7], link:user-manual.html[The Git User's Manual],
 908linkgit:gitworkflows[7]
 909
 910GIT
 911---
 912Part of the linkgit:git[1] suite